Ian Somerhalder and Nina Dobrev Ian Somerhalder and Nina Dobrev

Now that Elena has professed her love for Damon on the The Vampire Diaries, the big question is: How long before Damon messes it up?

"One of the big obstacles [for them], especially for Damon, is to make sure he doesn't f--- it up because he has a tendency to do that whether he means to or not," Nina Dobrev tells us in the video interview below from the show's Atlanta set. "He's going to try to be on his best behavior and Elena is going to embrace him, but she knows who he is and sometimes that comes to the surface and reminds her. But they'll try to figure it out because love prevails and they want their love to conquer all. They have gone through so much to get to where they are now. If they didn't keep fighting for it, it would be a shame."

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Last season, Elena experienced the biggest change of her life by becoming a vampire. From there, things went downhill. First, she lost her brother Jeremy (Steven McQueen) and then had her emotions turned off. After Elena finally hit rock bottom, she regained some humanity, leading to the ultimate swoon-worthy moment between her and Damon (Ian Somerhalder). But at the start of Season 5, the couple, certainly still in the honeymoon phase, will be hit with a number of challenges, including a lost-distance romance, new enemies at college, an evil villain they think is Stefan (Paul Wesley), and then the ultimate devastation when Elena learns that her previous love has been suffering all summer long.

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"She knows she's in love with Damon, but she still cares for Stefan and wants to make sure he's OK," Dobrev recently told us. "When she finds out what he's been through, it's not easy for her."

Although it seems like the season is heading down its usual dark path, Dobrev says that at the beginning, at least, we'll see a "lighter" Elena.

"I've had so much fun playing Elena this season because she is lighter and happier," Dobrev says. "She's unaware of a pretty tragic thing that has happened, so she's not affected ... and it will go dark eventually, but right now she's carefree and fun-loving and excited about her new boyfriend and college."

Watch our interview for more from Dobrev on playing Katherine as a human and how Elena is finally embracing her vampire side.

The Vampire Diaries premieres on Thursday, Oct. 3 at 8/7c on The CW.

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